Plovdiv or Sofia?

Both are inland and have no beaches, so a swim means a pool or fresh water. Plovdiv's options are the rowing canal on the western edge and the mountain reservoirs of the Rhodopes. Sofia has Pancharevo lake and the park pools, and the Black Sea is further from the capital, a full day's drive against several hours from Plovdiv.

The two eat much alike: kebapche, shopska salad, clay-pot dishes and banitsa for breakfast, served in mehanas in both cities. Plovdiv has a slight edge because it sits in the middle of wine country. Mavrud and Rubin come from the surrounding Thracian Valley, and you can visit estates near Asenovgrad and Brestovitsa within the afternoon, while Kapana's small streets put modern bistros and craft beer within a few steps of each other.

Sofia adds summer tarator, boza with breakfast and the odd tavern with live folk music. Its lighter modern cooking clusters around Vitosha Boulevard. Neither city goes far beyond Balkan cooking, so come for honest meals and good wine rather than gastronomy.

Plovdiv's antiquity is more complete and more striking. The Roman theatre still faces out over the city from its hillside, the stadium opens up beneath the pedestrian street, and the early Christian mosaics in the two basilicas are a real highlight. Above it all, the cobbled Old Town of National Revival houses gives you a whole historic quarter to wander, not just a list of monuments.

Sofia has fine individual sights: Roman Serdica around the metro, the Rotunda of St George, the gold domes of Alexander Nevsky and, out at the foot of Vitosha, the UNESCO-listed frescoes of Boyana Church. Its National Museum of History and its Museum of Socialist Art go deeper on Thracian gold and the communist era. The streets in between are plainer, though, and the capital feels less like a single historic place.

Sofia has more to offer after dark. The bars around Shishman and Tsar Ivan Asen streets, the cellar bars beneath grand old buildings and a few electronic clubs give it enough range for several different nights out.

Plovdiv's evenings mostly happen in Kapana, where wine and craft beer bars fill the pavements on warm nights and students keep term-time busy. It is charming but small, and you are more likely to end the night over a glass of wine than to go dancing.

Sofia has a mountain on its doorstep. Vitosha rises above 2,200m right at the city's edge, and you can reach its forests, boulder rivers and summit trails on public transport and by gondola. The Seven Rila Lakes and the skiing at Borovets are within reach for a day, and the big South Park and Borisova Gradina give long walks without leaving town.

Plovdiv's own green space is its rocky tepeta, short climbs with rooftop views. The Rhodope gorges begin about 20km south, and Pamporovo and the Central Balkan range lie further out, but almost all of it calls for a car. The hot plain also means spring and autumn suit walking better than summer.

Plovdiv is the better base, because central Bulgaria lies all around it. Bachkovo Monastery and the Asenovgrad fortress are half an hour away, and Hisarya's Roman walls and the Thracian temple at Starosel are under an hour. Kazanlak's tomb, the Valley of Roses, Shipka and Koprivshtitsa all make a full day out. Wine estates dot the plain in between.

Sofia's outings are fewer and longer. Rila Monastery is the one not to miss, and Plovdiv itself is a two-hour trip east, with Koprivshtitsa and the Iskar Gorge for quieter days. In both cities, a hire car makes far more of this possible.

Plovdiv's long car-free main street makes it the easier of the two with a pushchair, and its simple outings are close together. Children can watch the singing fountains in the Tsar Simeon Garden in the evening, use the playgrounds and paths in Lauta park and along the rowing canal, and scramble around the Roman theatre. The catches are the steep Old Town cobbles and the midsummer heat.

Sofia's best family day is up a mountain, riding the gondola onto Vitosha and walking its forest trails. In town there is a hands-on science centre, the mineral halls of the Museum of Earth and Man, a modest zoo and playgrounds in Borisova Gradina and South Park. Broken pavements and high kerbs make getting around with a buggy harder than in Plovdiv.

Both centres are easy to explore on foot, but they work differently. Plovdiv runs along one long pedestrian spine with Kapana, the ruins and the museums just off it, so you rarely need transport at all, though the steep Old Town cobbles are tough on ankles.

Sofia is bigger and leans on its clean metro, which links the airport, the centre and the foothills of Vitosha, with trams and buses for the rest. Cracked pavements and Cyrillic-only signs away from the centre take a little getting used to.

Neither city is worth visiting for its shops, and both offer the same souvenirs: rose oil cosmetics, embroidery and pottery. Plovdiv's more interesting shopping is the small design studios and galleries in Kapana and the antique stalls on the climb to the Old Town. Sofia has a little more scale, with Vitosha Boulevard ending at the mountain, Troyan pottery in craft shops, the icon and curio flea market by Alexander Nevsky and the Zhenski Pazar produce market.

In Plovdiv, much of what you came for costs nothing. The Roman stadium under the main street is there for anyone walking past, and an evening in Kapana costs only what you drink. Guesthouses in the Old Town, mehana dinners with local wine and taxis are all inexpensive.

Sofia is just as easy on the budget, which is rare for a capital. Metro rides from the airport, central hotels and museum entry all cost little. The smarter bistros and cocktail bars charge a bit more but never feel expensive, and a day on Vitosha or at Rila Monastery adds little to the bill.

Sofia has the deeper programme across the year. The National Opera and Ballet, the Sofia Philharmonic at Bulgaria Hall, the big National Palace of Culture and the Ivan Vazov theatre keep something on most weeks, and Orthodox choral singing is a distinctive extra.

Plovdiv's scene is smaller and more local, but it has one thing Sofia can't match: opera and concerts on summer nights in the Roman theatre. Outside that season, its opera, philharmonic and jazz festival are modest, and its plays, like Sofia's, are in Bulgarian.

Neither city has a working historic bathhouse in the centre, so both rely on hotel spas and nearby spa towns. Sofia's mineral water is part of daily life, with locals filling bottles at the warm taps by the old Central Mineral Baths, and Bankya is half an hour away for a proper soak. Plovdiv offers aylyak instead, the local art of taking it slow under the plane trees, with Hisarya's mineral pools about 45 minutes out. Velingrad is within reach of both.